Напольная акустика — German Physiks PQS-402

The PQS-402 is the larger of the two PQS models in the Reference Series from German Physiks. The company designed it to come close to the performance of its bigger Loreley Mk III within a more compact cabinet, and it later provided the basis for the smaller PQS-302. Two carbon fibre DDD drivers handle everything above the bass, while a separate low-frequency system uses two 10-inch woofers and four 8-inch passive radiators. Production takes place by hand in Germany.

Key specs that matter

The operating principle is two-way with 360 degree radiation. Frequency response is 24 Hz to 24 kHz, sensitivity 88.4 dB for 1 W at 1 m and impedance 4 ohm. The crossover sits at 215 Hz. In the passive network the DDD section is filtered at 12 dB per octave electrically and 18 dB acoustically, and the woofer section at 18 dB electrically and 24 dB acoustically. Rated power handling is 450 W nominal and 750 W short term, with a maximum output level of 118 dB. Each unit measures 620 mm wide, 1,560 mm high and 750 mm deep and weighs 165 kg. German Physiks gives a room size range of 30 to 150 m2 and a 5 year warranty.

Engineering and use context

With the DDD drivers covering everything above the crossover, no crossover falls in the midrange. Their enclosures are small aluminium cylinders closed with MDF end-caps and filled with damping, which leaves almost no flat surface to resonate. The bass cabinets pair each fast 10-inch woofer with passive radiators so the low end can keep pace with the DDD pair. These cabinets are not bolted together but located by interlocking collars, an approach meant to reduce resonances. Their vertical walls are non-parallel, internal bracing adds stiffness, and Hawaphon, a polymer sheet whose cells are filled with fine steel shot, damps each panel. Build checks include inspection of parts before assembly, checks at each stage, a burn-in of at least 12 hours and a final physical inspection. Rear panel jumpers change treble output by -2 dB, flat, +2 dB or +4 dB around 8 kHz, and raise the bass by 5 dB or 10 dB around 65 Hz. Finishes include black or white polyester, carbon fibre, macassar, walnut cluster and pappel cluster veneer.

Pairing

A passive PQS-402 needs one amplifier per channel rated at no less than 200 W into the nominal load, connected through two sets of WBT nextgen terminals that also allow bi-wiring. The active option replaces the internal network with the factory-configured Emperor Extreme DSP crossover and calls for two amplifiers per channel, at least 140 W for the DDD section and 180 W for the woofers.

Alternatives

The German Physiks PQS-302 is the smaller Reference Series floorstander, using the same twin DDD drivers with two 8-inch woofers.